DESCRIPTION: (Applicant's Description) Estrogen mimics are among the xenobiotics found to cause reproductive impairment and cancer long after they have been released in the environment. The wide variety of compounds, which potentially can act as hormone mimics, precludes any detection strategies based on structure, and there are no analytical tools capable of detecting these compounds to date. We therefore propose to develop a rapid, nanobalance quartz crystal system to monitor estrogenic substances in the environment. Our goal is to attach the hormone-binding domain of the estrogen receptor to a piezoelectric crystal and determine its potential as a sensor for estrogenic substances. This application offers the development of a new biological analytic technique that could monitor estrogenic substances both in the environment and in food products.